In a principal aspect the present invention relates to a grease packing device, and more particularly to a device for lubrication of bearings by packing the bearings with an appropriate grease or lubricant.
Bearings for vehicles and the like are typically mounted in cylindrical shaped raceways packed with grease or other lubricant. The lubricant or grease in the bearing requires replenishment or replacement from time to time. Devices have been available for many years directed to the purpose of packing bearings with grease including, for example, devices as depicted in U.S. Pat. No. 1,995,542 for A Means for Packing Bearings; U.S. Pat. No. 2,210,478 for a Lubricator; and U.S. Pat. No. 2,439,888 for a Bearing Packer.
Devices of the type disclosed in the prior art usually include a pair of opposed frustoconical plates, one of the plates having a generally concave shape and the other having a generally convex shape, so that when the plates are arranged in opposed relationship they provide a housing. The bearing, which is to be lubricated, is positioned between the plates and grease or lubricant is pumped into the region between the plates to replenish or replace the grease or lubricant in the bearing.
The prior art references disclose various devices of this type. Nonetheless there has remained the need for an improved device for packing grease into a bearing and, in particular, into a cylindrical bearing of the type typically used in combination with an axle or a shaft.
Briefly, the present invention comprises a grease bearing packer which includes a cylindrical container into which a separate cylindrical stem member is positioned. The stem member thus includes a piston slidably fitted into the container. The surface of the piston comprises a concave, frustoconical bearing support plate having an upstanding, axially centered post with a through passage that permits injection of grease into the container through the stem member post to the underside of piston. A separate cap member, which includes a convex frustoconical plate, is positioned in opposed relation to the concave frustoconical plate or piston of the stem member and maybe threadably attached to the stem member in order to pull the piston up for refilling the cup with grease. The piston can be removed and the cup manually filled or an alternate way of filling the cup with grease is to attach a grease gun to the grease-gun fitting at the outer end of the stem and pump the unit full of grease. The piston must be pulled up for either method. Openings or passages in the piston surrounding the stem member post permit the flow of grease into the region between the frustoconical plates and thus into a bearing member retained between the plates. Pushing downwardly on the cap member forces the cap member and stem member downwardly in the container thereby causing grease or lubricant within the container to flow upwardly openings or through the passages and into the bearing. A dust cover is provided to fit over the assembly and protect the contents of the container including the stem member and cap member. A compression spring may be provided to provide axial force to the piston to break vacuum when the cup becomes empty to aid in removing the piston when refilling with grease.
Thus it is an object of the invention to provide an improved bearing lubricant packer device fabricated from a minimum number of component parts and capable of being utilized to lubricate bearings of various sizes.
It is a further object of the present invention to provide a method for manufacture of a bearing packer utilizing plastic materials including glass filled polypropylene and foamed polypropylene materials.
Yet another object of the invention is to provide an improved bearing packer device which incorporates a container for the grease or lubricant for the bearing with, a cylindrical stem member and cap member which fit into the container and hold the bearing in position as grease or lubricant is injected into the bearing.
A further object of the invention is to provide a bearing lubricant packer device which may be made from molded plastic materials by injection molding processes wherein distortion of the component parts of the device is minimized as a result of the design of the device.
Yet another object of the invention is to provide a bearing lubricant packer device which includes a dust cover for protection of the device and the contents of the device including the lubricant and/or grease contained therein.
Another object of the invention is to provide a bearing lubricant packer device which includes a means for injecting lubricant or grease into a container for ultimate disposition into a bearing held by the device.
These and other objects, advantages, and features of the invention will be set forth in greater detail in the description which follows.